Factors Associated With Cardiovascular Mortality After Complicated Mild to Severe Traumatic Brain Injury (TBI): A TBI Model Systems Study

Objective: To characterize factors associated with death due to cardiovascular causes following complicated mild to severe traumatic brain injury (TBI). Setting: Chart review or telephonic interviews. Participants: Participants enrolled in the TBI Model Systems database. Design: Retrospective. Main Measures: Primary cause of death due to cardiovascular causes coded with ICD-9 codes 390-459 or ICD-10 codes 100-199 (diseases of the circulatory system) on death certificates. A competing risk cause-specific Cox proportional hazards regression analysis was completed to identify demographic and injury-related factors associated with increased risk of cardiovascular-related mortality. Results: Overall, 15,370 participants were included. Overall, 2,770 (18.0%) individuals died, of which 595 (21.5%) died due to cardiovascular-related causes. Those who died due to cardiovascular causes were older (hazard ratio [HR] 1.08, 95% 1.07–1.09, P <.001), more likely to be male (HR 1.84, 95% CI 1.50–2.26, P <.001), divorced (HR 1.63, 95% CI 1.20–2.23, P = .002), and had lower functional independence measure motor scores (HR 0.99, 95% CI 0.98–0.99, P <.001). Individuals who identified as Asian/Pacific Islander (HR 0.21, 95% CI 0.08-0.55, P = .002), were employed (HR 0.65, 95% CI 0.46-0.90, P = .010), had private insurance (HR 0.77, 95% CI 0.60-0.99, P = .043), and had post-traumatic amnesia (PTA) duration >30 days (HR 0.71, 95% CI 0.55-0.92, P = .010) were less likely to die due to cardiovascular causes. Alcohol or drug use and education level were not significantly associated with death due to cardiovascular causes. Conclusion: Over 1 in 5 deaths following TBI were due to cardiovascular causes. Older age, male sex, being divorced, and having lower FIM motor scores are risk factors, whereas being employed, having private health insurance, and PTA >30 days are protective factors for cardiovascular mortality.